Apparatus for processing cord



Aug. 7,1945. G. P. BosoMwoRTl-l APPARATUS FOR PROCESSING CORD Filed May4, 1944 .NJ-MHD :NQS 2 1 E954 moho: maan man? .z .5z8 Swan Pzmzoo mn I..mv.mn.nmmmw..rz hnz8 @U zu azi F2 n zozE.. l :mi I! Q l @.39 v

:lwoo/wm GEORGE Q 'DOSOMWORTH" www Q, Q al x..

299m 1| zo.. a .OJEJ

Patented Aug. 7, 1945*` 2,381,398 i ArrAnA'rUs Fon PROCESSING com)George nl. Bosomworth, Akron, Ohio, assignor to The Firestone Tire &Rubber Company, Akron, `Ohio, a corporation of Ohio Application May 4,1944, Serial No. 534,127 (C1. zzz-59.5)

4 Claims.

This invention relates to means for processing cord, and especiallyrelates to apparatus for pro-v ducing 'improved rubber-reinforcing cord.

.. One process of the type relating to the present invention is thatwherein cord which is to be used as reinforcing in a fan belt isimmersed in a latex bath and then dried, the cord initially being drawnfrom one spool and ultimately being4 wound up upon a second spool.Ordinarily this process involves Athe use of a constant speed windupmechanism and tension is obtained on the cord by the use of a brake onthe letoff means that controls unrolling the cord from the spool onwhich it is initially wound. In this process, the factors of speed andtension of the cords are so interlocked that it is difficult to obtaineither to any predetermined figure, with any degree of accuracy.Furthermore, the tension on the cord at the wind-up means is equal tothe drag on the cord at the let-oft' means, pluswhateverintermediatefriction may develop between the two points. 'I'hismeans that the cord is subjected to a rather unknown or uncontrollablemaximum tension, with the tension, of course, on the cord varying atvarious places in the cord vprocessing apparatus.

It is an object of the present invention to provide a novel, improvedapparatus for processing,

cord uniformly to produce high tensile strength rubber-reinforcing cordof uniform properties.

Another object of the invention is to provide an uncomplicated cordtreating apparatus in which the wind-upspeed of the cord does notlcontrol the tensioning'of the cord as it is being treated. Afurtherobject of the invention is to provide v an easily operated, inexpensiveapparatus for processing vvarious portions of a continuous cord or otherelastic material, such as fabric, uniformly as it passes through theapparatus.

v The foregoing and other objects will be manliest as the specicationproceeds.

In the accompanying drawing:

Figure 1 is a diagrammatic elevation of one embodiment o f theinvention; and

Figure 2 is a diagrammatic plan View of.cord driving means oftheapparatus of Figure 1.

have the cord wound therearound in several convolutions so as to obtaina purchase, or grip on the cord. The rolls I3 have a plurality ofannular corrugations in their faces, as shown, but may comprise aplurality of narrow pulleys which are abutted on and turn with a commonshaft. One

`o1' the rolls I3 may be driven through a non-reversible Worm gear 34 byany suitable means, such as an induction motor 35, to rotate the rollata constant speed. Usually the second roll I3 is not positively drivenexcept by the cord passing therearound.

In being drawn from the spool II, the cord may passover a guide pulley I4,- and next pass to a liquid bath, in this instance latex I6, containedin a tank I5. The latex is of any suitable composition andy propertiesand may be either naturally or artificially created. 'I'he cord I0 isler around vertically aligned rolls I1 and I 8' while in the tank I5.Auxiliary rolls I9 under spring pressure hold the cord against the rollsI1 and I 8, as it passes therearound and cause a certain amount ofdeformation to facilitate impregnation. Wet cord from the tank I5 thenpasses around the rolls I3 which are 'adapted to advance the cordconvolutions along the rolls whereby the cord is led into the rolls atone end thereof and drawn off at the other end of same,

' as shown in Figure 2.

After the cord passes around the constant speed rolls I3, I3 it is thendrawn through a drying oven 22, and the cord is subjected to -a uniformconstant tensional 'pull set up thereon through rolls 23, 23, which aresimilar to the rolls I3 and also obtain a, purchase or grip on the cordI0. However, the rolls 23 diier from the rolls I3 in one material regardin that one of the rolls 23 usually is driven by a direct current,constant torque motor 36 which is of the permanent magnet type and has awound rotor. Since the radius of the rolls 23 is constant, the constanttorque motor sets up a constant tension on the cord so that, in allevents, the cord, as it Referring in detail to the accompanying drawing', there is shown a, vcontinuous length of cord I0, which originallyis wound upon a spool II, that is journaled on a shaft I2 and thatusually has a drag yor brake not shown) associated therewith to keep thecord taut as it is drawn from the spool. The cord I0 is drawn from thespool II by means of cylindrical rolls I3, I3 which are driven atconstant vspeed and which 23, has a constant tension exerted thereon,which tension is uniform through out any length of material processed. Afeature of the invention is that this tension is controlled solely bythe peripheral speed of the rolls 23 with relation to the peripheralspeed of the rolls I3. The motor driving the rolls 23 should have aconstant torque over a fairly wide speed range in order to maintainconstant tensionI on the cord I0.

Any suitable means may be used to heat the drying oven 22, thus acurrent of hot air may be latex 26. As the cord is drawn out of the bath26, it is led around a guide pulley 21 and into a drying oven 29, thecord being wound around av series of pulleys 28 suitably journaled inthe dry ing oven 29. Ordinarily the pulleys 28 should be verticallyspaced and be positioned at the end of the oven, as shown. The oven 29,may be` associated with or be part of the oven 22, and may be heated inany desired manner.

The dry cord from the oven 29 is led around a roller 3l and then to awind-up reel 32, which `has level Winding means 33 associated therewithto distribute cord evenly over the reel 32. A further feature of theprocess is that the reel 32 is driven by a motor 31 which has a constanthorsepower output over about at least a 3 to l speed range and whichexerts a constant tensional force upon the cord Il) between the rollers23, 23'

and the wind-up reel 32 and winds up the cord I at a speed equal to thelet-off lineal speed of the cord from the spool II plus the increase inlength of the cord due to its stretch under tension. The motor drivingthe reel 32 produces this tension upon the cord regardless of the amountof cord wrapped upon the reel, so that the radius of pull, or torque setup by the reel 32 may vary but the actual tensional force on the cordremains constant for a large increase over the original radius ofthereel 32; for example, an increase in diameter of the reel from 3 to I2inches due to the cord wound thereon. The wind-up rate is substantiallyconstant but varies slightly to compensate for slight variations in thedegree of stretch of the cord under the constant tension exertedthereon.

In the apparatus disclosed it is essential that the rolls I3 .be drivenat a constant speed and the rolls 23, 23 have a constant torque driveapplied thereto. Preferably, the reel 32 has a means of driving same sothat the pull set up on the cord and the wind-up rate of same issubstantially constant. One electrical motor that has proved suitablefor use as a driving means 31 for the reel 32 is a series type directcurrent motor with a large external resistance and with the field forthe motor being in series with the armature. Then by using a three phasealternating current driving motor 35 to drive the 'rolls I3, which motoroperates at the desired speed, the cord I0 Will be drawn off the spoolII at the desired rate, and the speed of the motor approaches but doesnot exceed the synchronous speed thereof. The non-reversible worm gear34 connecting the motor to the roll will not overrun the motor so as tochange the speed at which the cord is drawn off the spool I I.

It is generally desirable to apply the maximum tension to the'cordduring the heating step immediately following the initial dippingoperation, that is, between rolls I3, I3 and rolls 23, 23. A tension inthe order of 60 pounds has been found satisfactory in this stage whenthe cord being the higher tension existing in the cord between rolls I3and 23 is localized therebetween, and is not transmitted to the cordtraveling from rolls 23.A In the case of a conventional fan belt cord, atension in the order of 35 pounds has been found suitable to apply bymeans of the driven wind-up means 32.

Now it will be seen that the tensional force exerted on the cord in therst step of processing same is a known, controllable tension which can.be uniformly exerted on various lengths of cord.

" Furthermore, the rate of wind-up of processed cord upon 'theWind-upreels does not determine processed was a conventional cotton or rayonfan the tension'of the cord when wound up, nor does it control thetensional force set up on the cord during the rst stages of processingsame. lt will beseen that this principle applies to cord,

o'r fabric treating processes regardless of the specific steps of same,as long as the cord is to be tensioned and wound up or used at a ratewhich is .to be independent of the tensioning treatment of the cord butwhich sets up a substantially uniform tension and a uniform residualstretch in the cord.

From the foregoing it will he seen that an uncomplicated, easilyoperated apparatus is provided for processing various lengths of cord orfabric or the like uniformly. At the same time, the apparatus serves todivide, Vor separate the stretching of the cord from the wind-up rate ofthe cord, thereby providing two separate, controllable operations whichare exerted upon the cord.

The finished cord produced by the present invention has been found to beunusually uniform and of high quality. The cord may be produced toexhibit a' very high tensile strength, which does not vary appreciablybetween various lengths or among diierent lots of the processed cord.The cord also possesses more uniform cross-sectional dimensions thanconventional processed cord, and imparts a. longer useful life to arubber article, such as a fan belt, pneumatic tire or other reinforcedrubber article incorporating the cord.

While one embodiment Aof apparatus of the process of the invention hasbeen completely illustrated and described herein, it will be appreciatedthat modification may be made without departing from the scope of theinvention, as defined inthe appended claims.

' What is claimed is:

1. In apparatus for uniformly stretching rubber-reinforcing cord, meansdriven by a constant speed motor for propelling the cord, means drivenby a constant torque motor for thereafter applying a predeterminedstretching tension to the cord, a third means driven by a motor having aconstant power output for winding up the cord, said constant speed motordriving said rstnamed means through a non-reversible Worm gear, wherebythe cord is propelled at a constant rate which is independent of thethereafter applied predetermined tension.

2. In apparatus for processing cord, means driven by a. constant speedmotor through a nonreversible Worm gear for propelling the cord, meansdriven by a constant torque motor for thereafter applying apredetermined stretching tension to the cord, means for releasing aportion of said stretching tension ,from the cord, and an additionalmeans for advancing theV cord under a diminished but uniform tension.

3. In apparatus for processing cord, means driven by a motor forpropelling the cord, and a second means driven by a constant torquemotor for thereafter applying a predetermined stretching tension to :thecord, said first-named motor driving said first-named means throughanonreversible worm gear, whereby the cord is propelled at a constantrate which is independent of Ithe thereafter applied predeterminedtension.

4. .In apparatus for uniformly processing rubber-reinforcing cord, meansfor impregnating the stant torque motor for thereafter applying apredetermined` stretching tension to the cord, means for drying thec'ord under the stretching tension, means for releasing a portion ofsaid stretching ltension from the cord, an additional means foradvancing the cord under a diminished but uniform Itension, means forimpreg` nating the cord while under said diminished tension, and meansfor drying the cord while cord with latex, means driven by a constant 10under said diminished tension.

speed motor through a non-reversible worm gear for propelling the cord,means driven .by a con- .GEORGE P. BOSOMWORTH.

